Re: Early diets

Stanley Friesen (
Sun, 5 Jun 1994 04:12:12 GMT

In article <>,
<> wrote:
>>> Humans have intermediate intestines (adjusted for body
>re your statement above, why should the length of the intestine be
>adjusted for body length? It seems like a herbivore is going to need
> about the same amount of time to digest a given plant material, and thus
> a certain length gut, regardless of it's body size. . .


For one thing - how are you going to fit a gut the size of a cow's
in a squirrel?

It turns out that the critical factors are processing time and
minimal intake requirements. A large animal needs to eat (and
digest) more food per unit time than a small one. Since the
rate of break down and absorption and are limited by physiological
factors, this can only be accomplished by increasing the surface
area of the absorptive part of the gut - what we call the small
intestines in vertebrates.

Studies have in fact verified this - the gut length of animals with
similar diets in fact *is* closely correlated with body weight.
This is an observational fact - the regression line is known.

(I even participated in a replication of this experiment in
high school. We collected road kill and measure the gut lengths
and plotted the results against body weight for each of the
three broad diet categories: a high school experiment is
generally not exactly leading edge science).


May the peace of God be with you.